Stator frame assembly, stator assembly and stepper motor including the same

Abstract

A stator skeleton assembly, a stator assembly including the same, and a stepper motor including the same are provided. The stator skeleton assembly includes a skeleton and a first terminal block. The skeleton provides a winding space and a rotor cavity for winding winding wires, and the winding space and the rotor cavity have a common central axis. The first terminal block includes a first terminal block body, a plurality of first pin holes formed in the first terminal block body for installing terminal pins, and a first limiting portion. The first limiting portion has a first limiting plane perpendicular to the extension direction of the first pin hole, which is used to position a circuit board installed to the stator skeleton assembly through the terminal pin in the extension direction of the first pin hole. The distance between the first limiting plane and the first side surface is within the range of 0.5-2 mm. The first limiting plane of the first limiting portion limits the position of the circuit board in the extension direction of the first pin hole.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a stator skeleton assembly, a stator assembly including such a stator skeleton assembly, and a stepper motor including such a stator skeleton assembly. Background Art

[0002] Claw-pole stepper motors are widely used in the field of smart homes. The claw-pole stepper motor may include a housing and a stator assembly, a rotor assembly, and a gear assembly installed inside the housing. The stator assembly includes a stator frame assembly, a first corresponding pole plate having a plurality of first corresponding pole claws, and a second corresponding pole plate having a plurality of second corresponding pole claws. The stator frame assembly includes a first frame portion, a first pole plate having a plurality of first pole claws matched with the plurality of first corresponding pole claws, a second pole plate having a plurality of second pole claws matched with the plurality of second corresponding pole claws, and a second frame portion.

[0003] As people's quality of life improves, the market requirements for product defect rates in the smart home field are very high. The current defect rate of claw-pole stepper motors has been controlled at around 10PPM, but it still cannot meet the more stringent requirements of special customers, who even pursue zero defects. At present, one of the defects that occurs in claw-pole stepper motors is the problem of winding wire breakage. Summary of the invention

[0004] At least one embodiment of the present disclosure provides a stator skeleton assembly, including a skeleton and a first terminal block. The skeleton provides a winding space and a rotor cavity for winding winding wires, and the winding space and the rotor cavity have a common central axis. The first terminal block includes: a first terminal block body, which protrudes from one end wall of the skeleton in the direction of the central axis and has a first side surface away from the central axis; a plurality of first pin holes formed in the first terminal block body for installing terminal pins, and the plurality of first pin holes extend substantially parallel to the radial direction of the winding space and the rotor cavity and open to the first side surface; and a first limiting portion, which protrudes away from the central axis relative to the first side surface and has a first limiting plane perpendicular to the extension direction of the first pin hole, and is used to position the circuit board installed to the stator skeleton assembly through the terminal pin in the extension direction of the first pin hole. The distance between the first limiting plane and the first side surface is in the range of 0.5-2mm.

[0005] For example, in some embodiments, the first limiting portion protrudes from the first side surface in the extending direction of the first pin hole.

[0006] For example, in some embodiments, the first terminal block further includes a wire passage groove that is recessed in a direction toward the central axis to provide a wire passage space for wires connected to the circuit board to pass through.

[0007] For example, in some embodiments, the wire groove has a groove bottom surface that is perpendicular to the extension direction of the first pin hole, and the distance between the groove bottom surface and the first limiting plane is in the range of 1.5-4 mm.

[0008] For example, in some embodiments, the first terminal block further includes a wall portion protruding in the direction of the central axis from a portion of the first terminal block body away from the central axis, and the wire passing groove is at least partially formed in the wall portion.

[0009] For example, in some embodiments, the height of the first terminal block body protruding from the end wall in the direction of the central axis is in the range of 1.5-3.5 mm, and the height of the wall portion protruding from the end wall in the direction of the central axis is in the range of 6.4-7.5 mm.

[0010] For example, in some embodiments, the length of the mating section of the pin hole for mating with the terminal pin is 2-9 times the hole diameter of the pin hole.

[0011] For example, in some embodiments, the length of the mating section of the pin hole for mating with the terminal pin is in the range of 1.5-3.5 mm.

[0012] For example, in some embodiments, the pin hole has a diameter in the range of 0.4-0.7 mm.

[0013] For example, in some embodiments, the first terminal block further includes an exhaust hole communicating with the first pin hole, the exhaust hole and the first pin hole extending in different directions and opening to the outside of the first terminal block.

[0014] For example, in some embodiments, the length of the first pin hole is in the range of 2.5-4.5 mm.

[0015] For example, in some embodiments, the stator frame assembly further includes: a first pole plate including an annular first plate-like body and a plurality of first pole claws, the plurality of first pole claws being bent from the first plate-like body and extending in the direction of the central axis; a second pole plate including an annular second plate-like body and a plurality of second pole claws, the plurality of second pole claws being bent from the second plate-like body and extending in the direction of the central axis; and a second terminal block. The second terminal block includes: a second terminal block body; a second pin hole formed in the second terminal block body and extending in parallel with the first pin hole; and a second stopper protruding from the second terminal block body and having a second stopper plane flush with the first stopper plane. The skeleton comprises: a first skeleton part, which comprises a first proximal wall close to the first pole plate, a first distal wall away from the first pole plate and a first cylindrical side wall, the first proximal wall and the first distal wall respectively extend radially outward from both ends of the first side wall, so that a first winding space is formed between the first proximal wall and the first distal wall; and a second skeleton part, which comprises a second proximal wall close to the second pole plate, a second distal wall away from the second pole plate and a second cylindrical side wall, the second proximal wall and the second distal wall respectively extend radially outward from both ends of the second side wall, so that a second winding space is formed between the second proximal wall and the second distal wall, and the winding space comprises a first winding space and a second winding space. Wherein, the first proximal wall, the first plate-shaped body, the second plate-shaped body and the second proximal wall are stacked in sequence to form a rotor cavity, and a plurality of first pole claws extend to the inner side of the first side wall and a plurality of second pole claws extend to the inner side of the second side wall. The second terminal block body is connected between the first proximal wall and the second proximal wall and is located outside the first plate-shaped body and the second plate-shaped body in the radial direction.

[0016] At least one embodiment of the present disclosure provides a stator assembly, comprising the stator frame assembly as described above, terminal pins, and a circuit board. The terminal pins are welded to the circuit board.

[0017] At least one embodiment of the present disclosure provides a stator assembly, comprising the stator frame assembly as described above, a terminal pin, a circuit board, and a cover. The terminal pin is welded to the circuit board. The cover covers the first terminal block from a side away from the rotor cavity. The cover comprises a cover wall, which abuts against the wall portion in the direction of the central axis.

[0018] At least one embodiment of the present disclosure provides a stepper motor including the stator assembly as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope of protection. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A perspective view of a stator skeleton assembly according to an embodiment of the present disclosure is shown;

[0021] Figure 2 Another perspective view of a stator skeleton assembly according to an embodiment of the present disclosure is shown;

[0022] Figure 3 shows a side view of a stator skeleton assembly according to an embodiment of the present disclosure;

[0023] Figure 4 A longitudinal cross-sectional view of a stator skeleton assembly according to an embodiment of the present disclosure is shown, which is cut along a central axis and a plane where pin holes are located;

[0024] Figure 5 A perspective cross-sectional view of a first electrode plate and a second electrode plate according to an embodiment of the present disclosure is shown;

[0025] Figure 6 A perspective view showing a stator frame assembly and terminal pins mounted to the stator frame assembly according to an embodiment of the present disclosure;

[0026] Figure 7 A top view showing a stator skeleton assembly and terminal pins mounted to the stator skeleton assembly according to an embodiment of the present disclosure;

[0027] Figure 8 A cross-sectional view of a stator frame assembly and a terminal pin mounted to the stator frame assembly according to an embodiment of the present disclosure is shown, wherein Figure 7 The line QQ in is intercepted;

[0028] Fig. 9 A perspective view showing a stator frame assembly and terminal pins and a circuit board mounted to the stator frame assembly according to an embodiment of the present disclosure;

[0029] Fig.10 An exploded perspective view showing a stator frame assembly and terminal pins and a circuit board mounted to the stator frame assembly and wires connected to the circuit board according to an embodiment of the present disclosure;

[0030] Fig.11A cross-sectional view of a stator frame assembly and terminal pins and a circuit board mounted to the stator frame assembly and wires connected to the circuit board according to an embodiment of the present disclosure is shown, wherein a first terminal block is provided with a wire passing groove;

[0031] Fig.12 A top view showing a stator frame assembly and terminal pins and a circuit board mounted to the stator frame assembly and winding wires according to an embodiment of the present disclosure;

[0032] Fig.13 A top view showing another stator frame assembly and terminal pins and a circuit board mounted to the stator frame assembly and winding wires;

[0033] Fig.14 A cross-sectional view showing another stator frame assembly and terminal pins and a circuit board mounted to the stator frame assembly and wires connected to the circuit board, wherein the first terminal block is not provided with a wire passing groove;

[0034] Fig.15 A cross-sectional perspective view of a stator skeleton assembly, a housing, and a cover member according to an embodiment of the present disclosure is shown;

[0035] Fig.16 A cross-sectional plan view of a stator skeleton assembly, a housing, and a cover member according to an embodiment of the present disclosure is shown;

[0036] Fig.17 A perspective view of a stator skeleton assembly according to another embodiment of the present disclosure is shown;

[0037] Fig.18 A table illustrating the relationship between the pull-out force of the pin hole of the stator skeleton assembly according to an embodiment of the present disclosure and the matching length and hole diameter of the pin hole is shown;

[0038] Fig.19 A table illustrating the relationship between the distance between the limiting plane of the stator frame assembly and the corresponding side surface and the occurrence rate of winding wire breakage is shown; and

[0039] Fig. 20 A table is shown which illustrates the relationship between the distance between the groove bottom surface of the wire slot of the stator frame assembly and the limiting plane and the occurrence rate of winding wire breakage.

[0040] Reference numerals list

[0041] First frame portion 110 Wall portion 240

[0042] First distal wall 111 Third side surface 241

[0043] First proximal wall 112 snap-fit ​​wall 250

[0044] First side wall 113 Exhaust hole 260

[0045] First winding space 118 counterbore 270

[0046] Second frame part 120 wire groove 280

[0047] Second distal wall 121 Groove bottom surface 281

[0048] Second proximal wall 122 Second terminal block 300

[0049] Second side wall 123 Second terminal block body 310

[0050] Second winding space 128 Second side surface 311

[0051] First electrode plate 130 Second pin hole 320

[0052] The first plate-shaped body 131 and the second limiting part 330

[0053] First pole claw 132 Second limiting plane 331

[0054] Second electrode plate 140 Terminal pin 400

[0055] Second plate-shaped body 141 Circuit board 500

[0056] Second pole claw 142 winding wire 600

[0057] First terminal block 200 Wire 700

[0058] First terminal block body 210 Second corresponding pole claw 810

[0059] First side surface 211 Housing 820

[0060] Fourth side surface 212 Cover member 900

[0061] First pin hole 220 Cover wall 910

[0062] The first limiting portion 230

[0063] The first limiting plane 231 DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0065] Unless otherwise defined, the technical or scientific terms used in the present disclosure shall have the usual meanings understood by persons with ordinary skills in the field to which the present disclosure belongs. The words "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Up", "down" and the like are only used to indicate relative alignment. When the absolute alignment of the described object changes, the relative alignment may also change accordingly.

[0066] According to at least one embodiment of the present disclosure, a stator skeleton assembly is provided, which includes a skeleton and a first terminal block. The skeleton provides a winding space and a rotor cavity for winding winding wires, and the winding space and the rotor cavity have a common central axis. The first terminal block includes a first terminal block body, a plurality of first pin holes and a first limiting portion. The first terminal block body protrudes from an end wall of the skeleton in the direction of the central axis and has a first side surface away from the central axis. A plurality of first pin holes are formed in the first terminal block body for installing terminal pins. The plurality of first pin holes extend substantially parallel to the radial direction of the winding space and the rotor cavity and open to the first side surface. The first limiting portion protrudes away from the central axis relative to the first side surface and has a first limiting plane perpendicular to the extension direction of the first pin hole, which is used to position the circuit board installed to the stator skeleton assembly through the terminal pin in the extension direction of the first pin hole. The distance between the first limiting plane and the first side surface is in the range of 0.5-2mm.

[0067] The terminal pin is installed to the stator frame assembly by being inserted into the first pin hole. Then, one end of the winding wire wound around the winding space is wound around the terminal pin. The connecting portion of the winding wire between the terminal pin and the winding space is in a suspended and taut state. In the case where the circuit board is installed to the stator frame assembly through the terminal pin, the circuit board may contact the winding wire and exert pressure on the winding wire, especially the connecting portion of the winding wire, which may cause damage or disconnection of the winding wire. In the stator frame assembly according to an embodiment of the present disclosure, the first limiting plane of the first limiting portion limits the position of the circuit board in the extension direction of the first pin hole (i.e., the installation direction of the circuit board). Therefore, the pressure exerted by the circuit board on the winding wire is well avoided or reduced, the damage or disconnection of the winding wire is avoided, and the performance of the stator frame assembly is improved.

[0068] Figure 1 and Figure 2 shows a perspective view of a stator skeleton assembly according to an embodiment of the present disclosure, Figure 3shows a side view of a stator skeleton assembly according to an embodiment of the present disclosure, Figure 4 FIG. 2 shows a longitudinal cross-sectional view of a stator frame assembly according to an embodiment of the present disclosure, which is cut along the central axis L and the plane where the pin holes 220 and 320 are located. Figure 1-Figure 4 As shown, the stator frame assembly includes a frame, a first pole plate 130, a second pole plate 140, a first terminal block 200 and a second terminal block 300. The frame includes a first frame portion 110 and a second frame portion 120. The first frame portion 110, the first pole plate 130, the second pole plate 140 and the second frame portion 120 together form a rotor cavity V. In order to conveniently and clearly describe the stator frame assembly according to the present disclosure, the axial direction Z where the central axis L is located, the first radial direction X perpendicular to the axial direction Z, and the second radial direction Y perpendicular to the axial direction Z and the first radial direction X are defined, and the rotor assembly matched with the stator assembly rotates around the central axis L in the rotor cavity V.

[0069] Figure 5 A three-dimensional cross-sectional view of a first pole plate 130 and a second pole plate 140 according to an embodiment of the present disclosure is shown, wherein the first pole plate 130 and the second pole plate 140 are stacked together. The first pole plate 130 includes an annular first plate-like body 131 and a plurality of first pole claws 132. The plurality of first pole claws 132 are integrally bent from the first plate-like body 131 to extend in the axial direction Z. Similarly, the second pole plate 140 includes an annular second plate-like body 141 and a plurality of second pole claws 142. The plurality of second pole claws 142 are integrally bent from the second plate-like body 141 to extend in the axial direction Z. For example, the first pole claws 132 and the second pole claws 142 can be formed by bending a pole plate preform by a stamping process, respectively, and the pole plate preform can be formed by a blanking process.

[0070] like Figure 5 As shown, the first plate-shaped body 131 of the first pole plate 130 and the second plate-shaped body 141 of the second pole plate 140 are stacked together to form a middle plane A between the first plate-shaped body 131 and the second plate-shaped body 141. A plurality of first pole claws 132 are arranged at intervals around the central axis L, a plurality of second pole claws 142 are arranged at intervals around the central axis L, and the first pole claws 132 and the second pole claws 142 are arranged to be staggered with each other in the circumferential direction. For the convenience and clear description of the stator frame assembly according to the present disclosure, the direction toward the middle plane A is defined as the proximal direction, and the direction away from the middle plane A is defined as the distal direction. The plurality of first pole claws 132 and the plurality of second pole claws 142 extend from the first plate-shaped body 131 and the second plate-shaped body 141 toward the distal direction, respectively.

[0071] return Figure 1-Figure 4The first skeleton part 110 includes a first proximal wall 112 close to the middle plane A, a first distal wall 111 far from the middle plane A, and a first side wall 113 connecting the first proximal wall 112 and the first distal wall 111. The first side wall 113 is cylindrical, and the first proximal wall 112 and the first distal wall 111 extend radially outward from the first side wall 113 at the proximal side and the distal side of the first side wall 113, respectively, to form a first winding space 118 between the first proximal wall 112 and the first distal wall 111. The second skeleton part 120 includes a second proximal wall 122 close to the middle plane A, a second distal wall 121 far from the middle plane A, and a second side wall 123 connecting the second proximal wall 122 and the second distal wall 121. The second side wall 123 is cylindrical, and the second proximal wall 122 and the second distal wall 121 extend radially outward from the second side wall 123 at the proximal side and the distal side of the second side wall 123, respectively, to form a second winding space 128 between the second proximal wall 122 and the second distal wall 121. The winding wire 600 can be wound around the first side wall 113 in the first winding space 118, and can be wound around the second side wall 123 in the second winding space 128.

[0072] The first proximal wall 112, the first plate-shaped body 131, the second plate-shaped body 141, and the second proximal wall 122 are stacked in sequence to form the rotor cavity V, so that the plurality of first pole claws 132 extend to the inner side of the first side wall 113 and the plurality of second pole claws 142 extend to the inner side of the second side wall 123. Specifically, the plurality of first pole claws 132 may abut against the inner wall surface of the first side wall 113, and the plurality of second pole claws 142 may abut against the inner wall surface of the second side wall 123.

[0073] The first terminal block 200 includes a first terminal block body 210, a plurality of first pin holes 220 formed in the first terminal block body 210, a first stopper 230 and a wall portion 240. The first terminal block body 210 protrudes from the first distal end wall 111 of the first skeleton portion 110 in the direction of the central axis L (upward in the figure) and has a first side surface 211 away from the central axis L. The plurality of first pin holes 220 extend substantially parallel to the radial direction and open to the first side surface 211. In this example, the first pin holes 220 are 3 and are arranged at uniform intervals. Obviously, the first pin holes 220 may have other numbers and arrangements. For example, the first pin holes 220 may be greater than 3. For example, the first pin hole 220 may also open to a fourth side surface 212 opposite to the first side surface 211, rather than a blind hole. The first stopper 230 protrudes from the first side surface 211 in the extension direction of the first pin hole 220 and has a first stopper plane 231. The first limiting plane 231 is perpendicular to the extension direction of the first pin hole 220, and is used to position the circuit board 500 (to be described later) mounted to the stator skeleton assembly through the terminal pin 400 in the extension direction of the first pin hole 220. In this example, the first limiting portion 230 is cylindrical. In addition, in this example, there are two first limiting portions 230, and they are respectively arranged on both sides of the plurality of first pin holes 220. Obviously, the first limiting portion 230 may have other numbers or positions, and the first limiting portion 230 may have other shapes. In addition, the first limiting portion 230 may also protrude from other surfaces, such as the third side surface 241 of the wall portion 240 to be described later, which is away from the central axis L, as long as it has a first limiting plane 231 for positioning the circuit board 500 in the extension direction of the first pin hole 220, and the present disclosure is not limited thereto. In this example, the height D2 of the first terminal block body 210 protruding from the first distal wall 111 in the direction of the central axis L is in the range of 1.5-3.5 mm, which ensures that the first terminal block body 210 has sufficient strength to avoid the terminal pin 400 from being offset when the terminal pin 400 is inserted into the first pin hole 220. In this example, the fourth side surface 212 of the first terminal block body 210 opposite to the first side surface 211 is a plane. In other examples, a recess may be provided in the fourth side surface 212, which helps to reduce the use of materials and reduce shrinkage. Fig.17 FIG. 2 shows a perspective view of a stator skeleton assembly according to another embodiment of the present disclosure. Fig.17 As shown, the fourth side surface 212 may be sawtooth-shaped.

[0074] The wall portion 240 extends from a portion of the first terminal block body 210 away from the central axis L in the direction of the central axis L (upward in the figure). The wall portion 240 includes a third side surface 241 away from the central axis L. For example, the third side surface 241 is flush with the first side surface 211. The height D3 of the wall portion 240 protruding from the first distal end wall 111 in the direction of the central axis L is in the range of 6.4-7.5 mm.

[0075] The second terminal block 300 includes a second terminal block body 310, a plurality of second pin holes 320 formed in the second terminal block body 310, and a second limiting portion 330. The second terminal block body 310 is connected between the first proximal wall 112 and the second proximal wall 122, and is located outside the first plate-like body 131 and the second plate-like body 141 in the radial direction. The second terminal block body 310 has a second side surface 311 that is away from the central axis L. For example, the second side surface 311 is flush with the first side surface 211. The second pin hole 320 extends parallel to the first pin hole 220 and opens at the second side surface 311. In this example, there are three second pin holes 320, but it is not limited thereto. The second limiting portion 330 protrudes from the second side surface 311 in the extension direction of the second pin hole 320 and has a second limiting plane 331. The second limiting plane 331 is flush with the first limiting plane 231. In this example, there are two second stoppers 330, which are respectively disposed on both sides of the plurality of second pin holes 320, but the present disclosure is not limited thereto. It should be noted that in some other embodiments, the stator frame assembly may include only the first terminal block 200, only the second terminal block 300, or other terminal blocks in addition to the first terminal block 200 and the second terminal block 300.

[0076] Figure 6 A perspective view of a stator frame assembly and terminal pins 400 mounted to the stator frame assembly according to an embodiment of the present disclosure is shown. Figure 7 4 is a top view showing a stator frame assembly and a terminal pin 400 mounted to the stator frame assembly according to an embodiment of the present disclosure, Figure 8 A cross-sectional view of a stator frame assembly and a terminal pin 400 mounted to the stator frame assembly according to an embodiment of the present disclosure is shown, wherein the stator frame assembly is Figure 7 The line QQ in is intercepted. Figure 6-8 As shown, the terminal pin 400 is installed to the stator frame assembly by being inserted into the first pin hole 220 and the second pin hole 320, and extends from the first side surface 211 and the second side surface 311 to the outside of the corresponding terminal block body 210, 310. Then, the winding wire 600 (see Fig.12) is wound around the portion of the terminal pin 400 extending to the outside of the terminal block body 210, 310 and the winding wire 600 wound around the terminal pin 400 can be fixed to the terminal pin 400 by welding. It should be noted that in other embodiments, the terminal pin 400 can have other shapes and arrangements. For example, the terminal pin 400 can also extend from the fourth side surface 212 of the first terminal block 200 opposite to the first side surface 211 to the outside of the first terminal block body 210.

[0077] like Figure 1 , Figure 2 , Figure 4 , Figure 7 and Figure 8 As shown, the first terminal block body 210 may also be provided with an exhaust hole 260 and a countersunk hole 270. The exhaust hole 260 is connected to the first pin hole 220 and extends to the outside of the first terminal block 200 in a different direction from the first pin hole 220, such as in a direction parallel to the central axis L. In this example, the first pin hole 220 is a blind hole. Therefore, when the terminal pin 400 is inserted into the first pin hole 220, the air remaining in the first pin hole 220 will be compressed and cannot be discharged, thereby making it difficult to insert the terminal pin 400, which will make the insertion depth of each terminal pin 400 less consistent and affect the winding of the winding wire 600. The exhaust hole 260 helps to exhaust the air when the terminal pin 400 is inserted into the first pin hole 220. In addition, in other examples, the exhaust hole 260 may also be provided in the second terminal block body 310.

[0078] The first terminal block body 210 of the stator skeleton assembly is also provided with a countersunk hole 270, which is arranged at the end of each first pin hole 220 in the first side surface 211. The depth of the countersunk hole 270 can be in the range of 0.2-0.5 mm. The countersunk hole 270 can have various shapes, such as square, circular, etc. In this example, the countersunk hole 270 is circular, and its diameter is larger than the diameter of the first pin hole 220, for example, in the range of 1-1.5 mm. In addition, the countersunk hole 270 can be provided with a chamfer at the connection position with the pin hole to guide the insertion of the terminal pin 400. In addition, the end of each second pin hole 320 can also be provided with a countersunk hole 270.

[0079] In this example, the first pin hole 220 includes a countersunk section, a matching section for matching with the terminal pin 400, and a vent section connected to the vent 260. The length h4 of the matching section can be 2-9 times the aperture of the first pin hole 220. For example, the aperture of the first pin hole 220 can be in the range of 0.4-0.7mm. For example, the length h4 of the matching section can be in the range of 1.5-3.5mm. For example, the total length h3 of the first pin hole 220 can be in the range of 2.5-4.5mm. In addition, the length of the matching section of the second pin hole 320 matching with the terminal pin 400 can be 2-9 times the aperture of the second pin hole 320. For example, the aperture of the second pin hole 320 can be in the range of 0.4-0.7mm. For example, the length of the matching section of the second pin hole 320 can be in the range of 1.5-3.5mm. For example, the total length of the second pin hole 320 can be in the range of 2.5-4.5mm. The hole diameter of the “pin hole” refers to the diameter of the pin hole 715 with a circular cross section, the diagonal distance of the pin hole 715 with a square cross section, and the maximum straight-line distance of the cross section of the pin hole 715 with other cross sections.

[0080] Fig.18 A table is shown that illustrates the relationship between the pull-out force of the pin holes 220, 320 of the stator frame assembly according to an embodiment of the present disclosure and the mating section length h4 and the hole diameter of the pin holes 220, 320. Fig.18 As shown in the table, when the length h4 and the hole diameter of the matching section of the pin holes 220 and 320 have such a size range, the pull-out force is greater than 9.80N, which can meet the pull-out force requirement.

[0081] When the winding wire 600 is welded to the terminal pin 400, the heat generated by the welding is conducted to the terminal block body at the pin holes 220 and 320 through the terminal pin 400, and the aperture of the pin holes 220 and 320 may become larger at high temperatures. Such a length of the matching section of the pin holes 220 and 320 allows the anti-pullout force between the terminal pin 400 and the pin holes 220 and 320 to be well maintained in a space with limited size, preventing the terminal pin 400 from being displaced under the action of external force, and improving the pull-off force of the terminal pin 400. In addition, the inventors recognize that when the length h4 of the matching section of the pin holes 220 and 320 increases to a certain extent, for example, greater than 3.5 mm, the pull-out force will be reduced. This is contrary to the general cognition of those skilled in the art. When the length h4 of the matching section of the pin holes 220 and 320 is greater than 3.5 mm, the pull-out force will be reduced because the terminal pin 800 will bend and deform when inserted into the pin holes 220 and 320.

[0082] Fig. 9A perspective view of a stator frame assembly and terminal pins 400 and a circuit board 500 mounted to the stator frame assembly according to an embodiment of the present disclosure is shown. Fig.10 An exploded perspective view of a stator frame assembly and terminal pins 400 and a circuit board 500 mounted to the stator frame assembly and electric wires 700 connected to the circuit board 500 according to an embodiment of the present disclosure is shown. Fig.11 A cross-sectional view of a stator frame assembly and terminal pins 400 and a circuit board 500 mounted thereto and wires 700 connected to the circuit board 500 according to an embodiment of the present disclosure is shown, wherein the first terminal block 200 is provided with a wire passing groove 280 . Fig.11 The image is cut along the center axis L and the plane where the pin holes 220 and 320 are located. Fig.12 FIG. 2 shows a top view of a stator frame assembly and terminal pins 400, a circuit board 500, and a winding wire 600 mounted to the stator frame assembly according to an embodiment of the present disclosure. Figure 9-12 As shown, one end of the winding wire 600 wound in the winding space is wound around the terminal pin 400, the circuit board 500 is mounted to the stator frame assembly through the terminal pin 400, and the terminal pin 400 is mechanically and electrically connected to the circuit board 500. For example, the terminal pin 400 can be inserted into the pin mounting hole in the circuit board 500 and fixed to the circuit board 500 by welding. The first limiting plane 231 of the first limiting portion 230 and the second limiting plane 331 of the second limiting portion 330 abut the circuit board 500 in the extension direction of the pin holes 220, 320, thereby positioning the circuit board 500 in this direction. Therefore, the distance between the circuit board 500 and the first side surface 211 or the second side surface 311 is defined by the limiting planes 231, 331.

[0083] Fig.13 FIG. 2 shows a top view of another stator frame assembly and terminal pins 400, a circuit board 500 and a winding wire 600 mounted to the stator frame assembly. Fig.13 As shown, the connection portion 610 of the winding wire 600 between the terminal pin 400 and the winding space is in a suspended and tight state. In the case where the circuit board 500 is mounted to the stator frame assembly through the terminal pin 400, the circuit board 500 may contact the winding wire 600 and apply pressure to the winding wire 600, especially the connection portion 610 of the winding wire 600, which may cause damage or disconnection of the winding wire 600.

[0084] In the stator skeleton assembly according to the embodiment of the present disclosure, the distance between the circuit board 500 and the first side surface 211 or the second side surface 311 is limited by the first limiting plane 231 and the second limiting plane 331. The first limiting plane 231 and the second limiting plane 331 limit the position of the circuit board 500 in the extension direction of the pin holes 220 and 320. Therefore, the pressure exerted by the circuit board 500 on the winding wire 600 is well avoided or reduced, the damage or disconnection of the winding wire 600 is avoided, and the performance of the stator skeleton assembly is improved. In the stator skeleton assembly according to the embodiment of the present disclosure, the distance h1 between the first limiting plane 231 and the first side surface 211 and the distance h1' between the second limiting plane 331 and the second side surface 311 can be in the range of 0.5-2mm. Such distances h1 and h1' are conducive to preventing the disconnection of the winding wire 600, avoiding the deformation of the terminal pin 400, and reducing the volume of the stator skeleton assembly. Fig.19 A table is shown to illustrate the relationship between the distances h1, h1' between the limiting planes 231, 331 of the stator frame assembly and the corresponding side surfaces and the occurrence rate of the winding wire 600 breaking. Fig.19 As shown, when the distances h1 and h1' are too small, for example, less than 0.5 mm, the winding wire 600 is prone to breakage. In addition, when the distances h1 and h1' are too large, for example, greater than 2 mm, the length of the terminal pin 400 is long, and the distance that the terminal pin 400 extends out of the pin holes 220 and 320 is large, which may cause the terminal pin 400 to bend and deform, which may affect the connection between the circuit board 500 and the terminal pin 400 and the pulling force of the terminal pin 400 in the pin holes 220 and 320. In addition, setting the distances h1 and h1' to less than 2 mm also helps to reduce the volume of the stator frame assembly and meet the installation size restrictions of the stepper motor.

[0085] In this example, the first limiting portion 230 and the second limiting portion 330 are both cylindrical, and the diameter h2 thereof is in the range of 0.5-3 mm, which ensures that the first limiting portion 230 and the second limiting portion 330 have sufficient strength to position the circuit board 500 .

[0086] In other examples, the first position limiting portion 230 and the second position limiting portion 330 may be of other shapes, and the two may have different shapes. In addition, the first position limiting portion 230 and the second position limiting portion 330 may also have other sizes.

[0087] return Figure 2 , Figure 4 , Figure 6-Figure 11The first terminal block 200 further includes a wire groove 280 formed in the first terminal block body 210 and the wall portion 240. The wire groove 280 is recessed from the first side surface 211 and the third side surface 241 in a direction toward the central axis L to provide a wire passing space for the wire 700 connected to the circuit board 500 to pass through. Fig.14 Another stator frame assembly and a cross-sectional view of a terminal pin 400 and a circuit board 500 mounted to the stator frame assembly and a wire 700 connected to the circuit board 500 are shown, wherein the first terminal block 200 is not provided with a wire slot 280. Fig.14 As shown, the wire 700 extends from the side of the circuit board 500 close to the terminal block into the space between the circuit board 500 and the third side surface 241. Then, the wire 700 is bent to extend outside the space. The wire 700 may abut against the first terminal block 200 to cause the circuit board 500 to shift away from the central axis L, and may even cause the circuit board 500 to loosen or disengage, or may cause the terminal pins 400 fixed to the circuit board 500 to disengage from the pin holes 220, 320, thereby causing the winding wire 600 to be disconnected. Increasing the distance h1 between the first limiting plane 231 and the first side surface 211 and the distance h1' between the second limiting plane 331 and the second side surface 311 helps to increase the wire passing space. In addition, the provision of the wire passing groove 280 helps to increase the wire passing space. In this embodiment, the wire groove 280 has a groove bottom surface 281 perpendicular to the extension direction of the first pin hole 220, and the distance D1 between the groove bottom surface 281 and the first limiting plane 231 and the second limiting plane 331 is within the range of 1.5-4 mm. Therefore, the wire passing distance is guaranteed in a limited space, avoiding undesirable phenomena such as the breaking of the winding wire 600 and the loosening of the circuit board 500. Fig. 20 A table is shown to illustrate the relationship between the distance D1 between the groove bottom surface 281 of the wire slot 280 of the stator frame assembly and the limiting plane 231, 331 and the occurrence rate of wire breakage of the winding wire 600. Fig. 20 As shown, when the distance D1 is less than 1.5, the winding wire 600 is easily broken. In addition, in order to reduce the volume of the stator frame assembly and considering the limitation of the installation size of the stepper motor, the distance D1 is preferably less than 4 mm.

[0088] According to an embodiment of the present disclosure, a stator assembly is further provided, which includes the stator skeleton assembly as described above. Fig.15 and Fig.16 8 and 9 show a cross-sectional perspective view and a cross-sectional plan view of a stator frame assembly, a housing 820 and a cover member 900 according to an embodiment of the present disclosure. Fig.15 and Fig.16As shown, the stator assembly also includes a first corresponding pole plate (not shown) having a plurality of first corresponding pole claws matched with a plurality of first pole claws, a second corresponding pole plate having a plurality of second corresponding pole claws 810 matched with a plurality of second pole claws, and a cover 900. The second corresponding pole plate can be integrated with the housing 820 of the stepper motor. The cover 900 covers the first terminal block 200 and the second terminal block 300 from the side away from the rotor cavity. In addition, the cover 900 includes a cover wall 910, which abuts against the wall portion 240 in the direction of the central axis L. Therefore, the cover 900, the first terminal block body 210, and the second terminal block body 310 well surround the space where the circuit board 500 is located, and foreign matter in the space can be prevented from entering the rotor cavity and affecting the performance of the stepper motor. The first terminal block 200 is also provided with two snap-fitting walls 250 for snap-fitting with the cover 900. The two snap-fitting walls 250 protrude toward the central axis L and toward the outside of the two sides on both sides of the fourth side surface 212 opposite to the first side surface 211.

[0089] According to an embodiment of the present disclosure, a stepper motor is also provided, which includes the stator assembly or the stator frame assembly as described above. In addition, the stepper motor may also include a rotor assembly, an output gear set, an output shaft assembly and a housing arranged in the rotor cavity.

Claims

1. A stator frame assembly, include: A frame, which provides a winding space for winding a winding wire and a rotor cavity, wherein the winding space and the rotor cavity have a common central axis; as well as The first terminal block comprises: A first terminal block body, which protrudes from an end wall of the frame in the direction of the central axis and has a first side surface facing away from the central axis; a plurality of first pin holes for mounting terminal pins formed in the first terminal block body, the plurality of first pin holes extending substantially parallel to the radial direction of the winding space and the rotor cavity and opening at the first side surface, the plurality of first pin holes being arranged at uniform intervals; and a first limiting portion, which protrudes away from the central axis relative to the first side surface and has a first limiting plane perpendicular to the extension direction of the first pin hole, and is used to position the circuit board mounted to the stator frame assembly through the terminal pin in the extension direction of the first pin hole, The distance between the first limiting plane and the first side surface is in the range of 0.5-2 mm.

2. The stator frame assembly according to claim 1, in, The first limiting portion protrudes from the first side surface in an extending direction of the first pin hole.

3. The stator frame assembly according to claim 1, in, The first terminal block further includes a wire passing groove that is recessed in a direction toward the central axis to provide a wire passing space for wires connected to the circuit board to pass through.

4. The stator frame assembly according to claim 3, in, The wire passing groove has a groove bottom surface which is perpendicular to the extension direction of the first pin hole, and the distance between the groove bottom surface and the first limiting plane is in the range of 1.5-4 mm.

5. The stator skeleton assembly according to any one of claims 3 or 4, in, The first terminal block further includes a wall portion protruding from a portion of the first terminal block body away from the central axis in the direction of the central axis, and the wire passing groove is at least partially formed in the wall portion.

6. The stator frame assembly according to claim 5, in, The height of the first terminal block body protruding from the end wall in the direction of the central axis is in the range of 1.5-3.5 mm, and the height of the wall portion protruding from the end wall in the direction of the central axis is in the range of 6.4-7.5 mm.

7. The stator skeleton assembly according to any one of claims 1 to 4, in, The length of the mating section of the pin hole for mating with the terminal pin is 2-9 times the diameter of the pin hole.

8. The stator skeleton assembly according to any one of claims 1 to 4, in, The length of the mating section of the pin hole for mating with the terminal pin is in the range of 1.5-3.5 mm.

9. The stator skeleton assembly according to any one of claims 1 to 4, in, The diameter of the pin hole is in the range of 0.4-0.7 mm.

10. The stator skeleton assembly according to any one of claims 1 to 4, in, The first terminal block further includes an exhaust hole communicating with the first pin hole, the exhaust hole extending in a different direction from the first pin hole and opening to the outside of the first terminal block.

11. The stator skeleton assembly according to claim 10, wherein, the length of the first pin hole is in the range of 2.5 - 4.5 mm.

12. The stator skeleton assembly according to any one of claims 1 - 4, further comprising: a first pole plate, which includes an annular first plate - like body and a plurality of first pole claws, the plurality of first pole claws being bent from the first plate - like body and extending in the direction of the central axis; a second pole plate, which includes an annular second plate - like body and a plurality of second pole claws, the plurality of second pole claws being bent from the second plate - like body and extending in the direction of the central axis; and a second terminal block, which includes: a second terminal block body; a second pin hole formed in the second terminal block body and extending parallel to the first pin hole; and a second limiting portion protruding from the second terminal block body and having a second limiting plane flush with the first limiting plane, wherein, the skeleton includes: a first skeleton part, which includes a first proximal wall close to the first pole plate, a first distal wall far from the first pole plate, and a cylindrical first side wall, the first proximal wall and the first distal wall respectively extending radially outward from both ends of the first side wall, so that a first winding space is formed between the first proximal wall and the first distal wall; and a second skeleton part, which includes a second proximal wall close to the second pole plate, a second distal wall far from the second pole plate, and a cylindrical second side wall, the second proximal wall and the second distal wall respectively extending radially outward from both ends of the second side wall, so that a second winding space is formed between the second proximal wall and the second distal wall, the winding space including the first winding space and the second winding space, wherein, the first proximal wall, the first plate - like body, the second plate - like body, and the second proximal wall are stacked in sequence to form the rotor cavity, and the plurality of first pole claws extend to the inside of the first side wall and the plurality of second pole claws extend to the inside of the second side wall, and wherein, the second terminal block body is connected between the first proximal wall and the second proximal wall and is located outside the first plate - like body and the second plate - like body in the radial direction.

13. A stator assembly, comprising the stator skeleton assembly according to any one of claims 1 - 12, the terminal pins, and the circuit board, wherein, the terminal pins are welded to the circuit board.

14. A stator assembly, comprising the stator skeleton assembly according to claim 5 or 6, the terminal pins, the circuit board, and a cover, wherein, the terminal pins are welded to the circuit board, the cover covers the first terminal block from a side far from the rotor cavity, and the cover includes a cover wall, and the cover wall abuts against the wall portion in the direction of the central axis.

15. A stepper motor comprising the stator assembly according to claim 13 or 14.

Images